1. Field of the Invention
The present invention relates to a method and apparatus for preventing a bill or the like from being pulled out, and more particularly relates to a method and apparatus for preventing a bill or the like from being pulled out by an illegal act from a bill processing machine such as automatic vending machine and money exchanger. In this specification and claims, the term "bill" is referred to a paper money and the like valuable sheet material.
2. The Prior Art
Generally, such a money processing machine is provided with a bill or paper money discriminating unit and a bill accumulating unit. The discriminating unit discriminates an inserted genuine bill from a counterfeit one, and the bill accumulating unit accumulates only genuine bills accepted in a bill accumulating box. Bills are conveyed by means of conveyor belts or the like from an inlet slot along a bill passage to the bill accumulating box. During this transportation, it is judged by the bill discriminating unit whether or not the bill inserted is genuine or counterfeit. Conventionally, a shutter plate is provided to block the bill passage for the purpose of preventing a genuine bill, which has passed the discriminating unit, from being drawn back to the bill inlet slot by an illegal act.
However, in the bill processing machine according to the conventional method, the shutter plate may be manually retreated by inserting an elongated thin plastic plate into the bill passage through the bill inlet slot. Thus, there is a problem in that bills accepted in the bill processing machine are liable to be illegally drawn back in such a manner.